Tool sharpening and gauging machine



Jan. 6, 1942. J. F. McCARTHY, JR

I TOOL SHARPENING AND GAUGING MACHINE Filed March 31, 1939.

3 Sheets-Sheet l F-i-I "illlllll. J. 6 M n 1 a A... u H 1" 4 6 n a i l2' w F a w a a m a m a a m a u 0 u m m m a 5 a a I" F o a a 2 1 6 a a z3 h a n o i 5 JAMES F. MC CARTHY, JR.

Gttomeg Jan. 6, 1942.

J. F. M CARTHY, JR 2,268,714

TOOL SHARPENING AND GAUGING MACHINE I Filed march :51, 1939 3Sheets-Sheet '2 lumentor C(ttomeg Jan. 6, 1942. J. F. McCARTHY, JR

TOOL SHARPENING AND GAUGING MACHINE Filed March 31, 1939 5 Sheets-Sheet3 I l I WIH'HHFUI IH H lnni flul G A a m m 1 I I 'III lllll'lllllll I 3m 9 8 u M 5 4 4 JAMES F. no GARTHY, JR.

Inventor dim-neg Patented Jan. 6, 1942 UNI-Ten stars-s Parem "or iesTOOL SHARPEN IN G AND GAUGING MACHINE James McCarthy, Jr.,, Wallace,Idaho Application March 31, 1939, Serial'No. 265,249

14- Claims.

My present'invention relates to improvements in tool sharpening andgauging machines for detachable bits of the type commonly used in rockdrilling and mining.

In mining the drilling machine operator will take a quantity'of bits to.the heading where he is to work'and where he has been provided with anumber of different lengths of drill rods. The bits are fitted-to therods and used until they become dull. The cutting edges will be batteredand distorted sothat they are of no further use for drilling purposes intheir present condition. Economical mining requires that the maximum ofuse be obtained from such bits, and therefore resharpening of the dulledbits is highly desirable. To be effective, such resharpening must beaccomplished simply and efiiciently due to the low initial cost of suchbits. When the cutting edges of the bits have been resharpened, thegauge faces, of the bit must also be re-gauged to insure accurateworkmanship in subsequent drilling. Due to the. extreme hardness of thesteel used in the detachable bits, I have found that sharpening andgauging may best be done when the bit has been heated. to a high degreeof temperature.

An important object of my invention istoprovide a precision bitsharpening and gaugingmachine, adjustable to accommodate various typesand'sizes of-bits.

Another object of my machine is the provision of means whereby the bitto be sharpened may be handled while at a high heat.

A further object of the invention is the provision of a bit holder whichwill readily receive and securely hold the bit. while it is beingpresented to the facing tools.

Still another object of the invention resides in the features of themachine whereby it may be quickly and conveniently adjusted to sharpenand gauge difierent sized bits.

A still further object of the invention has been the provision of such amachine as has been described-that maybe produced, installed: andoperatedatthe lowest possible cost, to permit the resh'arpener tocompete favorably with the original producer.

Other objects and advantages of the invention will'be apparent duringthe course of the following description.

In the accompanying drawings, forming a part of this specification, andin which like numerals are, employed to designate like parts throughoutthe Same,

i holder of my machine with tor stand upon which the motor II I surfacea pair of V-ways lE-I'S'.

Figure l is a side elevation of the millingmachine embodying myinvention,

Figure 2 is a front elevation of my machine,

Figure 3 is an enlarged detail view of the bit 7 portions broken awayfor the convenience of illustration,

Figure 4 is a view of a portion of the bit holder of my inventionillustrating the bit-clamping action therein, 7

Figures 5 and 6 are, respectively, side and end views of a typicaldetachablexbit to which my machine is adapted for sharpening andgauging, and a Figure 7 is a view in elevation of the bit holder arm,showing the manner in which a bit is fitted thereon. I I

- In the drawings, wherein for the purpose of illustration is shownthepreferred embodiment of my invention, the numeral III designates amois securely mounted. Upon the shaft IZ of' the motor I mount therotary sharpening miller I3.

A base plate I4 is provided and extends to one side of the stand I0,andhas'upon its upper A slidable motor carriage I6 is supported on "theplate I4' and is longitudinally slidable, guided upon the ways I5. Aboss I7, at one edge of the plate I4, supports a carriage screw I8secured tothe carriage I6 by means of the boss I9. outwardly from thecarriage and parallel to the plate I4 and is provided with elongatedslots 2 I2 I, and anchor bolts 2222 pass through the slots 2| and arethreaded into the plate I4 for securely anchoring the carriage in anadjusted position.

The carriage IB- is substantially triangular in elevation and at itsupper apex is provided with hinge ears 23- 23 which support a pivot pin24. An adjustable motor mounting plate 25 is pivotally supported fromthe pin 24, and a gauge screw 26 in the opposite end of the plate 25serves to adjust the angle of the plate with relationship to the rearsloping wall 21 of the carriage. A

motor 28 is mounted on the plate 25, and upon the motor shaft 29 issecured for rotation the gauging miller 30.

A carriage slide BI is supported from one face of the stand ID bymeansIof the arm 32, and the bit holder carriage 33 is slidably engagedthereon, as may best be seen in Figures 1 and 3. Depending from each ofthe longitudinal edges of the carriage 33 are flanges 34 which engagethe side edges and a portion of the under surface Of the member '3I andare provided with set A flange 20 extends screws 35 for securely lockingthe carriage in adjusted position.

Upon the upper surface of the carriage is mounted a pair of bearings 36and 31. A shaft 38 is fitted in the bearings for rotation. A collar 39is fixed to the shaft 38 between the bearings and carries an upstandingtubular arm 40. The flanged bushing 4| is fitted into the open end ofthe arm. A ball thrust bearing 42 in the lower depth of the arm 40 takesthe thrust of the pin 43, upon which pin is formed a bit holding head44. The pin 43 is grooved at 45, and a keeper screw 45 engages thegroove to hold the pin within the arm 40 and also the bushing 4|.

A collar 45 is secured to an overhanging end of the shaft 38 andsupports an arm 41 extending at right angles thereto. A dolly supportbushing 48 is slidably mounted upon this arm and has an upper slopingcam surface 49. A cam 50 is also provided on the arm 41 and has a lowercam surface and the cam operating handle 52 extends outwardly from thebushing 58.

An expansion spring 53 encircles the arm 41 and is retained in placeupon the upper surface of the bushing 50 by means of the spacer collar54 and the nut 55 threadably engaged with the arm 41. Between the dollybushing 48 and a fixed collar 56 I provide a return spring 51 which alsoencircles the arm 41.

A dolly supporting arm 58 extends from one side of the bushing 48 andcarries the dolly head 59. By means of suitable bearings 68-458, a dollymandrel 6! is mounted for rotation within the head 59; At the upper endof the mandrel I form a crank 62 for rotating the mandrel, which has atits lower end a dolly .63. The dolly 63 may be substantially round andtapered and has bit engaging points 64 and a centering point 65.

The carriage 33 at its rear end has an upstanding ear 66, and the slide3| has an ear or boss 61. A carriage screw 68 is rotatably mounted inthe ear 66 and threaded in the boss 61 and may be turned by means of thetoggle-handle 69.

Referring now to Figures 5 and 6, wherein I have illustrated, in sideand face views, a typical drill bit, it will be apparent that the bitconsists of an interiorly threaded body portion having a lower skirt 1|,and four radial extending wings as 12, 13, 14 and 15. The upper impactfaces of the wings are tapered to form a cutting edge 16. The outer faceof the wing at the largest diameter is ground to form gauge faces 11.

The rotary sharpeningmiller I3 is circular and has sloping cutting faces18 and 19 tapering outwardly from the center.

Referring to Figure 1, I have shown an upstanding bar 80 secured to theback of the collar 46 which protrudes sufficiently high so that theupper end is located directly behind the bushing 48, Lug 8| on thebushing 48 in certain positions abuts against the bar 80 and impedesfurther rotation of the bushing 48 on the arm 41, to align the dolly 63with the bit to be gauged.

Method of operation Before starting the operation of sharpening andgauging bits, the dull bits are sorted for size and type and are heatedin a suitable furnace to approximately 1600 degrees F. Certain types ofbits require a taper on the gauge face of approximately 3 degrees. Thistaper varies with other types of bits as well as in accordance withvarying conditions to be met. To adjust the gauging miller the operatorwill loosen the anchor screws 22 and unlock the carriage screw l8. Byturning the carriage screw la the carriage I6 is slid forward or back tothe desired location, whereupon it may be again securely locked againstmovement.

To vary the angle of the beveled gauging miller the gauge screw 26 isturned one way or the other to increase or decrease the angle betweenthe adjustable motor mount 25 and the rear face 21 of the carriage, itbeing apparent that the mount 25 swings pivotally on the pin 24.

Because the depthof the bit, measured by the distance between theextreme edge of the skirt 1| and the cutting edges 16, varies withdifferent bits, it is occasionally necessary to adjust the swinging bitholder so that the bit will be presented to the sharpening miller l3 inthe proper manner. To accomplish this adjustment the carriage 33 ismoved on the slide plate 3| after loosening the set screws 35 by turningthe carriage screw 68 to either advance or withdraw the carriage asdeemed advisable.

To sharpen a bit the operator removes it from a furnace with a pair oftongs and places it upon the head 44. It will be understood that thedolly collar is swung out of the way, as may be seen in the dotted lineposition indicated in Figure 2. The tubular arm 46, carrying the bit tobe sharpened, is presented to the miller I3 with the tapered faces ofthe miller 18 and 19 cutting or dressing the tapered upper faces of thewings of the bit. The miller cutting faces in this operation areinterposed between a face of each of the adjoining. angularly disposedwings of the bit. Whentheproper out has been taken the operator indexesthe bit on the h'ead 44 to successively present the other faces of thebit for sharpening.

When the bit has been properly sharpened on the miller l3, the dolly andits mandrel and crank are swung from the dotted line position of Figure2 to the solid line position shownin Figures 2 and 3, so that the lug 8|contacts the stop bar 89. The cam 50 is now turned from the positionshown at Figure 3 to that in Figure '4 to depress the dolly bushing 48on the arm 41 and cause the dolly to engage the cuttingfaces of the bit.

It is customary that bits of the type herein being treated will beprovided with a central water hole, in which case the centering pin 65will enter the water hole. Of course, for bits of the type that do nothave a central water hole a centering pin will be omitted from thedolly.

By turning the mandrel 6| through the operation of the crank 62, the bitmay be readily revolved on the tubular arm 40, the thrust being taken bythe ball bearing 42.

The operator now swings the complete unit, comprising the shaft 41, thearm 40 and the crank 62, to the dotted line position of Figure l, and inthis way presents the faces 11 of the bit to me beveled miller 30 forgauging. Suitable stops may be provided to support the weight of the bitholder unit, and it will of course be apparent that the stops may bemade adjustable so that various positions will result.

To gauge the bit the operator merely cran'ks the mandrel and the dolly63 so that successively the different faces 11 will be presented to thegauge miller 30. I

Upon the completion of the gauging operation the bit holder unit isreturned to the upright position, the cam 58 is released, and the spring51 will lift the dolly bushing 48, together with the dolly :63 out ofengagement with the bit. By swinging the dolly and its bushing 48 on thearm the bit may readily be lifted 'ofi the pin '44 andreturned to thefurnace for additional heating in preparation for tempering or for-amhealing, or if the heat is 'still sufficiently high the bit-may bequenched at this time.

It is to be understood that the 'form of my invention, herewith'shownand described, is to be taken as a'preferre'd example of the same, andthat various changes in the shape, size and arrangement of parts may beresorted to without departing from the spirit of my invention or thescope of the subjoined claims. --'What I claim .as new and desire tosecure by Letters Patent is:

.1. In a drill bitsharpening'machine, the combination vof a basestructure, arotary driven sharpening miller supported, thereon, acarriage slide supported from a base structure adjacent the sharpeningmiller, a slidable carriage operable with'said slide, a bit holderswingingly mounted upon the carriage in alignment with the sharpeningmiller, a rotary driven gauging miller supported from said base in thepath of the swinging bit holder, a rotatably mounted head for engagingthe cutting face of a bit upon said bit holder when the latter is swungto present such bit to said gauging miller, and means to 110- tate saidhead during the gauging operation.

2; In a drill bit sharpening machine, the comupon swinging movement ofthe bit holder-arm, a

bination of a base structure, a rotary driven I sharpening millersupported thereon, a slidable carriage supportedadjacent the sharpeningmiller, a bit holder swingingly mounted upon said carriage in alignmentwith the sharpening miller, a rotary driven gauging miller supportedfrom said base in the path of the swinging bit holder, a rotatablymounted head for engaging the cutting face of a bit upon said bit holderwhen the latter is swung to present such bit to said gauging miller, andmeans to rotate said head during the gauging operation.

3. In a drill bit sharpening machine, the combination of a basestructure, a rotary driven sharpening miller supported thereon, a bitholder swingingly mounted on said base structure and comprising atubular arm and a rotatable pin having a head for the reception of a bitto be sharpened, a rotary driven gauging miller sup ported from saidbase in the path of the swinging bit holder, a rotatably mounted headfor engaging the cutting face of a bit upon said bit holder when thelatter is swung to present such bit to said gauging miller, and means torotate said head during the gauging operation.

4. In a drill bit sharpening machine, the com bination of a basestructure, a rotary driven sharpening miller supported thereon, aslidable carriage supported adjacent the sharpening miller and providedwith hearing blocks, a shaft mounted in said bearing blocks, a bitholder comprising a collar on the shaft, a tubular arm extendinglaterally from said collar, and a bit receiving pin rotatable withinsaid arm; a rotary driven gauging miller supported from said base in thepath of the swinging bit holder, a rotatably mounted head for engagingthe cutting face of a bit upon said bit holder when the latter is swungto present such bit to said gauging miller, and means to rotate saidhead during the gauging operation.

5. In a drill bit sharpening machine, the combination of a basestructure, a rotary driven er arm swingingly :mounted on said basestructure in alignment with the sharpening miller, a rotary drivengauging miller mounted on said base in the path of a swinging bitholder, a dolly arm parallel 'to the bit holder arm and movable arotatably mounted head on said dolly arm-- for engaging the cutting faceof a bit upon said bit holder when the latter is swung to present suchbit to said gauging miller, and meansto .rotate said head duringthegauging operation.

6. In a drill bit sharpening machine, the combination of a basestructure, a rotary driven sharpening miller supported thereon, a bit"holder arm swingingly mounted on said base structure inalignment withasharpening miller, a rotary driven gauging miller supported from saidbase in the path of the swinging bit holder, a

dolly arm mounted to swing parallel to'the bit holder arm, a bushing onsaid dolly arm, a rotatably mounted head on saidbushing for en gagingthe cutting face of a bit upon said bit holder when the latter is swungto present such bit to said gauging -miller1and means to rotate saidhead during the gauging; operation.

7; In a drillbi't sharpening machine, the combination of abasestructure, a rotary driven sharpening miller supported erarmswingingly mounted on said base structure in alignment with thesharpening miller, a rotary driven gauging miller supported fromsaidbase in the'path of the swinging bit holder, a dolly arm mounted toswing parallel to the bit holder arm, a spring pressed bush-ing on saiddolly arm, means on said arm for depressing'said bushing on occasion, arotatably mounted head on said bushing for engaging the cutting face ofa bit upon said bit holder when the latter is swung to present such bitto said gauging miller and means to rotate said head during the gaugingoperation.

8. In a drill bit sharpening machine having a base structure supportingrotary driven sharpenarm for engaging the cutting face of a bit uponsaid bit holder when the latter is swung to present such bit to saidgauging miller, and means to rotate said head during the gauging operation.

'9. In a drillbit sharpening machine having a base structure supportingrotary driven sharpening and gauging millers thereon, the combination,of a bit holder swingingly supported from the base and comprising apivot shaft, means swinging laterally from said shaft for receiving andsupporting a bit, a dolly arm also extending laterally to said shaft andadapted to swing parallel to said bit receiving and supporting means, arotatably mounted head on said dolly arm for engaging the cutting faceof a bit upon said bit holder when the latter is swung to present suchbit to said gauging miller and means to rotate said head during thegauging operation.

10. In a drill bit sharpening machine having a base structure supportingrotary driven sharpthereon, a bit *hold- I 4- ening and gauging millersthereon, the combination of a bit holder swingingly mounted on the basein alignment with said millers and comprising a pivot shaft, a bitholder arm radially swingable about the axis of said shaft and adaptedto receive a bit to be sharpened, a dolly arm also swingable about theaxis of said shaft parallel to the bit holder arm, a spring-pressedbushing on said dolly arm, a cam bushing on said arm cooperable withsaid spring-pressed bushing for depressing the latter against theurgence of its spring, a rotatably mounted head on said bushing forengaging the cutting face of a bit upon said bit holder when the latteris swung to present such bit to said gauging miller at which time thespring-pressed bushing is depressed through rotary motion of the cambush ing and means to rotate said head during the gauging operation.

11. In a drill bit sharpening machine having a base structure supportingrotary driven sharpening and gauging millers thereon, the combination ofa bit holder swingingly mounted on the base in alignment with saidmillers and comprising a pivot shaft, a bit holder arm extending at anangle from said shaft and adapted to receive a bit to be sharpened, adolly arm extending from said shaft to swing parallel to the bit holderarm, a spring pressed bushing'on said dolly arm, a cam on said arm fordepressing the bushing, a collar supported from said bushing, a mandrelmounted in said collar and having a crank on one end, and a dollymounted on the mandrel and adapted to engage and turn a bit on itssupporting arm during the gauging operation.

12. In a drill bit sharpening machine, a bit holder mounted for'swingingmovement, a dolly arm spaced from-and'swingable parallel to the bitholder and movable therewith, a dolly support pivotally mounted on thedolly arm and having a cam face, a spring-pressed cam mounted on thedolly arm, yieldable means acting upon the dolly support to urge itagainst the cam, a rotary headfor engaging a bit mounted on the bitholder upon depressive movement of the cam, and means for rotating saidhead during the gauging operation.

13.111 a drill bit sharpening machine, a bit holder mounted for swingingmovement, a-dolly arm spaced from and swingable parallel to the bitholder and movable therewith, a dolly support mounted upon said dollyarm and comprising a pivotal bushing having a cam face, a springpressedcam having means for rotation mounted on the dolly shaft, yieldablemeans acting upon said bushing to urge it against the cam, a rotatablehead supported from said bushing for engaging a bit mounted on the bitholder upon depressive movement of the cam, and means for rotating saidhead during the gauging operation.

14. A drill bit sharpening machine comprising a rotary driven sharpeningmiller, a bit holder swingingly mounted in alinement with saidsharpening miller, a rotary driven gauging miller mounted in the path ofsaid swinging bit holder, a rotatably mounted head for engaging thecutting face of a bit upon said bit holder when l the latter is swung topresent such bit to said gauging miller, and means to rotate said headduring the gauging operation.

JAMES F. MCCARTHY, JR.

